SU559921A1 - Method for preparing phthalimidines - Google Patents

Description

1de Ri and Ra are hydrogen, alkyl, aryl, hydroxyaryl, alknlaryl or Ri + R2 - benzylidene, by the interaction of the corresponding phthalides with ammonia.

Production of phthalimindins by the proposed method is possible even with the use of aqueous ammonia solutions, although it was previously believed that the presence of water in the synthesis of amides or lactams is undesirable.

This method is a general method for the preparation of various phthalimidines not substituted with nitrogen from the corresponding phthalides. The method makes it possible to obtain phthalimidines, which cannot be obtained or can be obtained by known methods, for example, 3,3-diaryl-phthalimidines, which do not contain ionization groups in aryl substituents, are obtained by the proposed method; 3,3-di- (p-tolyl) -phthalimidine, 3- (phenyl) -3- (p-tolyl) -phthalimidine, 3,3-di (3,4-xylyl) -phthalimidine.

The proposed synthesis method is not accompanied by side reactions and, in almost all cases, allows to obtain pure

phthalimidines that do not require additional purification.

Phthalide reactions can be carried out with both aqueous and non-aqueous (e.g. alcoholic) ammonia solutions, as well as using organic or ammonia solutions.

Note: After chromatography on alumina (benzo.h, benzene-ether, benzene-ethanol).

Solvents, smears and water-miscible solvents. In dependence on the structure of the initial phthalide and the structure of the final product obtained, the interaction occurs at a temperature of from 20 to 300 ° C, preferably prOO-ZOO C. An increase in the concentration of ammonia solutions promotes an increase in the output of phthalimidines.

Example 1. 1.0 g of phthalide and 3 ml of an aqueous ammonia solution (d 0.903 g / cm-) are loaded into a glass (or steel) ampoule. The reaction is carried out with stirring at 180 ° C for 18 hours. After assuring the reaction, the precipitate is filtered off, washed with a small amount of water and dried under vacuum at 60 ° C. The result is phthalimidine in the form of white crystals with m. Pl. 152-153 ° C; yield 0.85 g (85% of theoretical).

In the other examples (see examples 2-II in the table), the synthesis and isolation of the reaction products is carried out in a similar way; In all cases where the solvent for crystallization is not indicated, melting points are given for products isolated directly from the reaction mass and not subjected to purification.

The table presents the conditions of the experiments and the results of examples 2-11.

b f o r m - l and invented and

The method of obtaining fthalim; 1 dinov General formula

R

V

NH

WITH

N

ABOUT

RI and R2 are hydrogen, alkyl, aryl, oxycarbonyl or - benzylidene,

reacting phthalps with ammonia,

characterized in that, in order to increase the yield and quality of the target product, the ynponteiii technology of the process and increase its selectivity, water is boosted and the reaction is carried out at 100-300 ° C.

Sources of information taken into account in the inventive ekyiertiza:

1. Hubacher MN and others. Laxatives: chemical structure and activity of phthaleins and oxyanthraquinones I. Ash. Pharm. Assoc. 42, 23 1953.

2. US Patent Le 2964533, cl 260-326, I960.

3.Dunet A. et al. Phthalimide Recovery Products Bull. Chem. Soc, 1956, 906.

4.Dent C. E. Production of tiifthalicanine related to porphyriam. I. Chem. Soc., 1938, 1 (prototype).